Physics Letters B最新文献

{"title":"Strange mesons with one dynamical gluon: A light-front approach","authors":"Jiangshan Lan ,&nbsp;Jialin Chen ,&nbsp;Zhimin Zhu ,&nbsp;Chandan Mondal ,&nbsp;Xingbo Zhao ,&nbsp;James P. Vary ,&nbsp;BLFQ Collaboration","doi":"10.1016/j.physletb.2025.139654","DOIUrl":"10.1016/j.physletb.2025.139654","url":null,"abstract":"<div><div>We obtain the mass spectra of strange mesons using a light-front quantized Hamiltonian with Quantum Chromodynamics (QCD) input, incorporating quark-antiquark and quark-antiquark-gluon Fock components, along with a three-dimensional confinement. We work within the basis light-front quantization framework. The resulting eigenvectors can simultaneously describe the kaon's electromagnetic form factor, decay constant, distribution amplitude, and quark and gluon distribution functions under QCD scale evolution. Using the obtained kaon parton distribution functions (PDFs), supplemented by established nuclear PDFs, we also predict the kaon-nucleus-induced Drell-Yan cross section, which is expected to be measured soon by COMPASS++/AMBER at CERN.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"868 ","pages":"Article 139654"},"PeriodicalIF":4.3,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144271586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Direct-photon production in inelastic and high-multiplicity proton–proton collisions at s= 13 TeV","authors":"","doi":"10.1016/j.physletb.2025.139645","DOIUrl":"10.1016/j.physletb.2025.139645","url":null,"abstract":"<div><div>In this letter, we present the first measurement of direct photons at the transverse momentum of <span><math><mn>1</mn><mo>&lt;</mo><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub><mo>&lt;</mo><mn>6</mn></math></span> GeV/<em>c</em> at midrapidity <span><math><mo>|</mo><mi>η</mi><mo>|</mo><mo>&lt;</mo><mn>0.8</mn></math></span> in inelastic and high-multiplicity proton–proton collisions at a centre-of-mass energy of <span><math><msqrt><mrow><mi>s</mi></mrow></msqrt><mo>=</mo></math></span> 13 TeV. The fraction of virtual direct photons in the inclusive virtual photon spectrum is obtained from a fit to the dielectron invariant mass spectrum. In the limit of zero invariant mass, this fraction is equal to the relative contribution of real direct photons in the inclusive real photon spectrum. Contributions from decays of light-flavour neutral mesons are estimated using independent measurements in proton–proton collisions at the same energy and the same event class. For the first time at the LHC energies, a direct-photon signal is observed at low <span><math><msub><mrow><mi>p</mi></mrow><mrow><mi>T</mi></mrow></msub></math></span> in both inelastic and high-multiplicity event classes, with a significance of 3.2<em>σ</em> and 1.9<em>σ</em> in terms of standard deviations, correspondingly. The yield of direct photons in inelastic pp collisions is compared to perturbative QCD calculations. The integrated photon yield is studied as a function of charged-particle multiplicity and is compared to the results from other experiments and theoretical calculations. The results show a significant increase of direct-photon yield with charged-particle multiplicity.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"868 ","pages":"Article 139645"},"PeriodicalIF":4.3,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144304816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Equivalence of f(Q) cosmology with quintom-like scenario: The phantom field as effective realization of the non-trivial connection","authors":"Spyros Basilakos ,&nbsp;Andronikos Paliathanasis ,&nbsp;Emmanuel N. Saridakis","doi":"10.1016/j.physletb.2025.139658","DOIUrl":"10.1016/j.physletb.2025.139658","url":null,"abstract":"<div><div>We show that <span><math><mi>f</mi><mo>(</mo><mi>Q</mi><mo>)</mo></math></span> cosmology with a non-trivial connection, namely the Connection II of the literature, is dynamically equivalent with a quintom-like model. In particular, we show that the scalar field arising from the non-linear <span><math><mi>f</mi><mo>(</mo><mi>Q</mi><mo>)</mo></math></span> form, and the scalar field associated to the non-trivial connection, are combined to provide one canonical and one phantom field in the minisuperspace Lagrangian. Hence, the combination of two well-behaved fields appears effectively as a phantom field. This is fundamentally different from the usual approach in phantom and quintom cosmology, in which the phantom field is introduced ad hoc, and thus it may open a new way to handle the phantom fields, namely as effective realizations of the connection-related canonical fields.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"868 ","pages":"Article 139658"},"PeriodicalIF":4.3,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144296998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gravitational waves from extreme mass ratio inspirals around rotating black holes surrounded by dark matter halo","authors":"Kun Meng ,&nbsp;Jiaqiang Zhao ,&nbsp;Meihua Deng ,&nbsp;Chong Li ,&nbsp;Nan Yang","doi":"10.1016/j.physletb.2025.139630","DOIUrl":"10.1016/j.physletb.2025.139630","url":null,"abstract":"<div><div>Dark matter (DM) has become one of the biggest mysteries in the universe. The next generation gravitatinal wave (GW) detector is designed to detect low-frequency GWs emanating from extreme-mass-ratio-inspiral systems (EMRIs), this provides possibilities to detect DM with low-frequency GWs. In this paper, we calculate the GWs emanating from EMRIs with central SBH being rotating BH surrounded by DM halo (DMBH) and study the effects of DM on the waveforms of GW. We give the orbit of the secondary body by Hamilton-Jacobi (HJ) method, and calculate GWs with numerical Kludge (NK) method. By comparing the waveforms of GWs of DMBH and that of Kerr BH, we find there exist dephasing between the two waveforms. Through calculating mismatch of the two waveforms it's found mismatch increases with the DM parameter <span><math><msub><mrow><mi>c</mi></mrow><mrow><mi>q</mi></mrow></msub></math></span> but decreases with the DM parameter <span><math><msub><mrow><mi>ω</mi></mrow><mrow><mi>q</mi></mrow></msub></math></span>. As <span><math><msub><mrow><mi>c</mi></mrow><mrow><mi>q</mi></mrow></msub></math></span> increases or <span><math><msub><mrow><mi>ω</mi></mrow><mrow><mi>q</mi></mrow></msub></math></span> decreases, the indistinguishable lower bound may be exceeded, then the gravitational waveforms of DMBH and that of Kerr BH are distinguishable. This allows to distinguish the GWs of DMBH from that of Kerr BH and constrain DM parameters with the observation data of the next generation GW detectors. In addition, the dephasing of the two waveforms is found to increase with the eccentricity of orbit, so more eccentric orbits will help to constrain the DM parameters further.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"868 ","pages":"Article 139630"},"PeriodicalIF":4.3,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144262195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Supercooled dark scalar phase transitions explanation of NANOGrav data","authors":"Francesco Costa ,&nbsp;Jaime Hoefken Zink ,&nbsp;Michele Lucente ,&nbsp;Silvia Pascoli ,&nbsp;Salvador Rosauro-Alcaraz","doi":"10.1016/j.physletb.2025.139634","DOIUrl":"10.1016/j.physletb.2025.139634","url":null,"abstract":"<div><div>The evidence of a Stochastic Gravitational Wave Background (SGWB) in the nHz frequency range is posed to open a new window on the Universe. A preferred explanation relies on a supercooled first order phase transition at the 100 MeV–GeV scale. In this article, we address its feasibility going from the particle physics model to the production of the gravitational waves. We take a minimal approach for the dark sector model introducing the fewest ingredients required, namely a new <span><math><mi>U</mi><mo>(</mo><mn>1</mn><mo>)</mo></math></span> gauge group and a dark scalar that dynamically breaks the symmetry. Supercooling poses challenges in the analysis that put under question the feasibility of this explanation: we address them, going beyond previous studies by carefully considering the effects of a vacuum domination phase and explicitly tracking the phase transition from its onset to its completion. We find that the proposed model can successfully give origin to the observed PTA SGWB signal. The strong supercooling imposes a correlation between the new gauge coupling and the scalar quartic one, leading to a significant hierarchy between the (heavier) gauge boson and the dark scalar. Ultimately, information on phase transitions from SGWB observations could provide a direct probe of the microphysics of the Early Universe and be used to guide future searches of dark sectors in laboratories.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"868 ","pages":"Article 139634"},"PeriodicalIF":4.3,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144262196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Entanglement and entropy uncertainty in black hole quantum atmosphere","authors":"Shuai Zhang,&nbsp;Li-Juan Li,&nbsp;Xue-Ke Song,&nbsp;Liu Ye,&nbsp;Dong Wang","doi":"10.1016/j.physletb.2025.139648","DOIUrl":"10.1016/j.physletb.2025.139648","url":null,"abstract":"<div><div>In this work, we investigate the properties of Hawking radiation induced by the quantum atmosphere beyond the event horizon, by considering two detectors in Schwarzschild spacetime with the parameterized Hartle-Hawking temperature. We explicitly study the dynamics of quantum entanglement and found that its characteristics are closely correlated with Hawking quantum radiation beyond the event horizon. Namely, its minimal value corresponds to the peak of Hawking radiation. By virtue of the mutual information, we demonstrate the complementary relationship of the information distribution in the black hole. In addition, we detailedly discuss the influence of distance from the center of black hole to particle, radius of event horizon and Hartle-Hawking constant on the entropy uncertainty in the current scenario, and the results interestingly show that there exists an opposite correlation between the entanglement and the entropy uncertainty. It is believed that our observation could provide a new perspective for understanding the black hole information paradox and black hole thermodynamics.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"868 ","pages":"Article 139648"},"PeriodicalIF":4.3,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144262132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurement-induced entanglement entropy of gravitational wave detections","authors":"Preston Jones,&nbsp;Quentin G. Bailey,&nbsp;Andri Gretarsson,&nbsp;Edward Poon","doi":"10.1016/j.physletb.2025.139628","DOIUrl":"10.1016/j.physletb.2025.139628","url":null,"abstract":"<div><div>Research on the projective measurement of gravitons increasingly supports Dyson's observations on the physical limitations of detecting single gravitons. It is therefore prudent to consider alternative signatures of non-classicality in gravitational wave detections to determine if gravity is quantized. Coincident multiple detector operations make it possible to consider the bipartite measurement-induced entanglement, in the detection process, as a signature of non-classicality. By developing a model of measurement-induced entanglement, based on a fixed number of gravitons for the bipartite system, we demonstrate that the entanglement entropy is on the order of a few percent of the mean number of gravitons interacting with the detectors. The bipartite measurement-induced entanglement is part of the detection process, which avoids the challenges associated with developing signatures of production-induced entanglement, due to the extremely low gravitational wave detector efficiencies. The calculation of normalized measurement-induced entanglement entropy demonstrates the potential of developing physically meaningful signatures of non-classicality based on bipartite detections of gravitational radiation. This result is in stark contrast to the discouraging calculations based on single-point detections.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"868 ","pages":"Article 139628"},"PeriodicalIF":4.3,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144239400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Calculation of the axial-vector coupling constant gA to two loops in covariant chiral perturbation theory","authors":"Véronique Bernard ,&nbsp;Jambul Gegelia ,&nbsp;Shayan Ghosh ,&nbsp;Ulf-G. Meißner","doi":"10.1016/j.physletb.2025.139637","DOIUrl":"10.1016/j.physletb.2025.139637","url":null,"abstract":"<div><div>We present a calculation of the leading two-loop corrections to the axial-vector coupling constant <span><math><msub><mrow><mi>g</mi></mrow><mrow><mi>A</mi></mrow></msub></math></span> in two covariant versions of two-flavor baryon chiral perturbation theory. Taking the low-energy constants from a combined analysis of elastic and inelastic pion-nucleon scattering, we find that these corrections are rather moderate.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"868 ","pages":"Article 139637"},"PeriodicalIF":4.3,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144239403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of pairing and neutron-excess on suppression of the above-barrier fusion cross-section in 19O + 12C","authors":"H. Desilets ,&nbsp;Rohit Kumar ,&nbsp;R.T. deSouza ,&nbsp;S. Hudan ,&nbsp;C. Ciampi ,&nbsp;A. Chbihi ,&nbsp;K.W. Brown ,&nbsp;K. Godbey ,&nbsp;B. Pinheiro ,&nbsp;E.N. Cardozo ,&nbsp;J. Lubian","doi":"10.1016/j.physletb.2025.139643","DOIUrl":"10.1016/j.physletb.2025.139643","url":null,"abstract":"<div><div>Fusion excitation functions for ¹⁹O and ¹⁹F + ¹²C were simultaneously measured along with ²⁰O + ¹²C using the active-target detector MuSIC@Indiana. Examination of the cross-section just above the barrier reveals a significant suppression of fusion for the ¹⁹O + ¹²C system starting at E<span><math><mmultiscripts><mrow><mo>∼</mo></mrow><mprescripts></mprescripts><mrow><mi>c</mi><mo>.</mo><mi>m</mi><mo>.</mo></mrow><none></none></mmultiscripts></math></span>12 MeV. This suppression is not simply due to the reduced binding of the unpaired neutron in ¹⁹O as ¹⁷O + ¹²C does not exhibit the same sharp suppression of the fusion cross-section. Multiple mean-field models are used as a reference to understand the measured fusion excitation functions.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"868 ","pages":"Article 139643"},"PeriodicalIF":4.3,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144239397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental constraints on seesaw parameters in the Wigner-like parametrization","authors":"Jihong Huang","doi":"10.1016/j.physletb.2025.139638","DOIUrl":"10.1016/j.physletb.2025.139638","url":null,"abstract":"<div><div>By introducing three right-handed neutrino singlets, the popular canonical seesaw mechanism is able to simultaneously explain the tiny masses of Majorana neutrinos and the baryon asymmetry of the Universe. In this paper, we provide an explicit calculation in this model with the help of the Wigner-like parametrization. We work in a special ansatz where both <span><math><msubsup><mrow><mi>m</mi></mrow><mrow><mi>D</mi></mrow><mrow><mi>†</mi></mrow></msubsup><msub><mrow><mi>m</mi></mrow><mrow><mi>D</mi></mrow></msub></math></span> and <span><math><msubsup><mrow><mi>m</mi></mrow><mrow><mi>R</mi></mrow><mrow><mi>†</mi></mrow></msubsup><msub><mrow><mi>m</mi></mrow><mrow><mi>R</mi></mrow></msub></math></span> are diagonal, with <span><math><msub><mrow><mi>m</mi></mrow><mrow><mi>D</mi></mrow></msub></math></span> and <span><math><msub><mrow><mi>m</mi></mrow><mrow><mi>R</mi></mrow></msub></math></span> being accordingly the Dirac and Majorana neutrino mass matrices, and <span><math><mo>[</mo><msubsup><mrow><mi>m</mi></mrow><mrow><mi>D</mi></mrow><mrow><mi>†</mi></mrow></msubsup><msub><mrow><mi>m</mi></mrow><mrow><mi>D</mi></mrow></msub><mo>,</mo><msubsup><mrow><mi>m</mi></mrow><mrow><mi>R</mi></mrow><mrow><mi>†</mi></mrow></msubsup><msub><mrow><mi>m</mi></mrow><mrow><mi>R</mi></mrow></msub><mo>]</mo><mo>=</mo><mn>0</mn></math></span> holds. Physical observables can be exactly calculated without any approximation, where three light Majorana neutrino masses <span><math><msub><mrow><mi>m</mi></mrow><mrow><mi>i</mi></mrow></msub></math></span>, leptonic mixing angles <span><math><msub><mrow><mi>θ</mi></mrow><mrow><mi>i</mi><mi>j</mi></mrow></msub></math></span>, CP-violating phases <span><math><mo>{</mo><mi>δ</mi><mo>,</mo><mi>ρ</mi><mo>,</mo><mi>σ</mi><mo>}</mo></math></span>, and three rotation angles <span><math><msub><mrow><mi>ϑ</mi></mrow><mrow><mi>i</mi></mrow></msub></math></span> describing the hierarchy between electroweak and seesaw scales are chosen as input parameters. For demonstration, we evaluate the branching fractions of the lepton-flavor-violating decays of charged leptons and the CP-violating asymmetries in the resonant thermal leptogenesis. The model parameters are constrained by the latest experimental limits.</div></div>","PeriodicalId":20162,"journal":{"name":"Physics Letters B","volume":"868 ","pages":"Article 139638"},"PeriodicalIF":4.3,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144239398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}